For years marine biologists have relied on dart biopsies – small portions of tissue obtained by shooting a dart into an animal – to study the genetics of dolphins in the wild. The trouble is that this method can’t be used on very young animals for fear of harming them, and concerns about injury to adult animals has made dart biopsies a controversial choice for field scientists. Now, as reported in the journal PLoS One an international team of marine biologists has found a new way to gather the same information, and it involves little more than collecting a dolphin’s exhaled breath.

As described by University of Queensland scientist Celine Frère and colleagues, the air expelled through dolphin blowholes – simply